1. Field of the Invention
The present invention relates to a drum washing machine, and more particularly, to a frame structure of a drum washing machine having improved rigidity characteristics of the frame so that the design of the drum washing machine can be variously modified.
2. Description of the Related Art
A drum washing machine washes laundry by rotating a drum-type washing tub using a motor so as to lift and drop the laundry and washing water and to generate friction between the laundry and the washing water. Generally, the drum washing machine includes a frame for forming the overall external appearance of the washing machine and supporting internal components, such as the drum-type washing tub.
As recent drum washing machines have been developed to have a large size and increase the rotational speed of the washing tub installed therein, the weights of the internal components and force generated and transmitted from a motor have increased. Accordingly, the research and development of a technique for maintaining and reinforcing the rigidity of a frame against dynamic excitation load generated from an internal rotating body as well as the rigidity of the frame against static load applied from the outside has been required. The present invention is designed to satisfy the above requirement.
Korean Patent Laid-open Publication No. 2004-74318 discloses a frame structure of a conventional drum washing machine.
As shown in FIG. 1, the frame structure of the conventional drum washing machine includes a main frame 1 including a rear frame 2 and two side frames 3, a first front frame 4 and a second front frame 5 positioned in front of the main frame 1 and respectively connected to upper and lower ends of the two side frames 3, and spring brackets 6 respectively connected to upper surfaces of the two side frames 3 for supporting springs buffering vibration generated due to the rotation of an internal component.
In the above frame structure of the conventional drum washing machine, the first front frame 4 and the second front frame 5 support only the upper and lower ends of the main frame 1. Accordingly, when external force is applied to the frame structure or rotary force from the internal rotating component is applied to the frame structure, the frame structure cannot maintain sufficient rigidity against distortion. Further, when concentrated load having a small area of force is applied between the first front frame 4 and the second front frame 5, the side frames 3 are easily warped.
Moreover, the frame structure of the conventional drum washing machine does not have frames installed on opened upper and lower portions of the main frame 1 for reinforcing the rigidity of the frame structure, thus having the low rigidity of upper and lower portions of the washing machine.
Consequently, the conventional drum washing machine requires sheathing members, such as a top cover 7 and a door panel 8, serving to maintain the rigidity. The sheathing members severely limit the design freedom of the drum washing machine so as to satisfy consumer's requirements.
In the conventional frame structure, the spring brackets 6 support only springs, and do not sufficiently reinforce the rigidity of the main frame 1, thus being incapable of sufficiently reinforcing the rigidity of upper corners of the main frame 1.
The above problem is severe, as drum washing machine products are large-sized and a rotating body in the drum washing machine products is rotated at a high speed. Accordingly, in order to upgrade the drum washing machine products and design the products to meet consumer's various requirements, this problem must be solved first.